This invention relates to an improvement of a buffer for vehicle, which is mounted between relatively movable members of the vehicle, for example between a cab or rear body and a chassis frame of motor truck, between a body and a frame of passenger car, or between a cab or coupler head and a frame of trailer truck.
Upon collision in an accident, a cab or rear body mounted on a frame is moved relatively to the frame as by being moved therealong by reaction of an impact force applied to a vehicle body, so that truck crews will be exposed to danger by crash of the cab against another outside object or by the forwardly moving rear body. To minimize the impact force applied to the vehicle, a shock absorber made of an energy absorbing member which is capable of plastic deformation has been mounted between a front bumper and the front end of the frame. However, the shock absorber is not sufficient to absorb the kinetic energy of the rear body due to an extra large inertia energy of the rear body (a cabin in case of a passenger car) created by the reaction of the impact force applied to the vehicle upon collision. Therefore, provision of the shock absorber is not sufficient to secure safety of the crews in the cab. The scheme to provide another appropriate energy absorbing means at the front and rear ends of the vehicle in addition to said shock absorber requires a fairly large size of the energy absorbing means and large spaces for mounting the means at the front and rear ends of the vehicle, which result in an increase of the size and gross weight of the vehicle and the manufacturing cost accordingly.